Stability analysis and design of an unmanned deformable vehicle during coupled reconfiguration motion

Abstract

An unmanned deformable vehicle, which is a new type of robot combining a car and a robot, can drive at high speed with wheels and walk with steps. An unmanned deformable vehicle is prone to tipping instability when reconfigured between the automotive and humanoid states. The following work reported herein addresses these issues. The kinematic model of an unmanned deformed vehicle during the coupled reconfiguration process was established. The zero moment point (ZMP) theory was used as the stability criterion, and based on the requirement for stability during the reconstruction process, a genetic algorithm was used to find the optimal value of the support state foot landing position for the parking and driving coupled reconfiguration, and for the optimal value of the driving acceleration of the deformed vehicle during the driving coupled reconfiguration. On the basis of the optimal foot landing position, the total reconfiguration time threshold, deformed vehicle driving acceleration threshold, and support surface tilt angle threshold were analysed and calculated in accordance with stability requirements during the reconfiguration. Finally, the stability performance of the optimised system was verified through prototype testing.